Apparatus for the treatment of plastic explosives for the production of ribbon- or rod-shaped pieces



Ma 3, 1938. H LLE 2,116,007

APPARATUS FOR THE TREATMENT OF PLASTIC EXPLOSIVES FOR THE PRODUCTION OFRIBBON OR ROD-SHAPED PIECES v Filed Feb. 26, 1936 2 Sheets-Sheet May 3,1938. BILLE APPARATUS FOR THE TREATMENT OF PLASTIC EXPLOSIVBS FORTHEPRODUCTIQN OF RIBBON OR ROD-SHAPED PIECES Filed Feb. 26, 1956 2Sheets-Sheet J /w iii- In Viv 17% H677 r/cfi 5/7/67 Patented May 3, 1938PATENT OF Fl-QE APPARATUS FOR THE TREATMENT OF PLASTIC EXPLOSIVES FORTHE PRODUC- TION OF RIBBON- LIIECES OR BOD-SHAPED Henrieh Bille, Saetrein Royken, Norway, assignor to Norsk Spraengstefindustri A/S, Oslo,

Norway Application February 26, 1936, Serial No. 65,914 In Norway March15, 1935 1 Claim.

Owing to the drawbacks and dangers connected with the extrusion ofplastic explosives through mouth pieces under high pressure, it has beenproposed to form masses of this kind into rods or strips by dividing arolled sheet of the mass into parallel, longitudinal strips.

As masses of this kind are very liable to stick together, and are alsoliable to stick to the surface on which they are conveyed, the furthertreatment of the mass strips or' rods after the division is accompaniedby certain difiiculties, which are avoided by means of the method andthe arrangements forming the subject matter of the present invention.

In accordance with the present invention the plastic mass is firstrolled in a known manner, so as to form a sheet of suitable thickness,and this sheet is then placed on a continuously moving conveyor surfaceon which it is divided into a suitable number of parallel strips bymeans of knives arranged at a suitable distance above the conveyorsurface. During or immediately after the cutting into strips the stripsare spaced apart, so that no contact can take place between two adjacentstrips.

This spacing of adjacent strips may be obtained in different ways, forinstance by conveying adjacent strips on to different conveyingsurfaces, which may be on the same or on different levels.

In case rotating, circular knives are used for the dividing operation,the spacing of adjacent strips may also be obtained by mounting thecircular knives on a rotating shaft alternately at a distance apartcorresponding to the breadth of the strips and a very small distance.

Between the circular knives, which are only a very small distance apart,there will be cut out a very narrow strip, which will remain between thecircular knives.

On the point of the circumference at which the knives arrive in contactwith the mass sheet on the conveyor, the part of the mass remainingbetween the two knives which are close together will be somewhatcompressed, so that an additional quantity of mass will be taken upbetween these circular knives, and this surplus of mass will spread outin both directions laterally approximately at the point where thecircumference of the circular knives again leaves the conveyor surface.

In this way the thin mass film usually connecting two adjacent stripswill be torn at this point, and the mass which is carried round with theknives will at the next turn be added to the normal strips and cut bymeans of the knives.

With this arrangement the strips leave the cutting knives spaced adistance apart corresponding approximately to the distance between theclosely adjacent circular cutting knives, and this distance issuflicient to prevent contact between the plastic strips owing to theunavoidable deformation of cross section taking place after thedivision.

On the drawings is diagrammatically illustrated some arrangements bymeans of which the present method may be carried out.

Figures 1 and 2 are a diagrammatical cross section and longitudinalsection on a larger scale of a particular form of cutting knives.

Figure 3 is a perspective view of some of the last mentioned cuttingknives during operation, Figure 4 is a. side view of a form of thecutting and spacing device, and Figures 5 and 6 are diagrammaticsections through two adjacent strips illustrating the manner in whichthese strips are conducted to different conveyors.

Referring to the drawings, I is a continuous conveyor belt the upperpart of which moves over a stationary surface and conducts the plasticmass 6 to circular knives 3 mounted in pairs closely together on aroller 'l, the said knives being adapted to cut up the sheet-like mass 5into strips of suitable breadth.

Knife roller 1 and the knives 8 may preferably be manufactured from amaterial such as synthetic resin, paraffin impregnated fiber mass or thelike, to which the plastic mass is not likely to stick.

With particular reference to Figures 4, 5 and 6, the strips H and I2after being out by means of the knife roller '1, 8 are conducted todifferent conveyors l3, I4 disposed in the same plane but moving inopposite directions. Every second strip is conducted to one conveyor l3and the other strips to the other conveyor M, this being effected byplacing on the roller 7 between the circular knives 8 narrow conveyingribbons l5, it, which run over ll, I8 placed on opposite sides of theroller 8.

The effect of this arrangement as indicated on Figures 5 and 6 is toconduct the strips I I onto the conveyor 13 and the strips 12 onto theconveyor M, the cutting of said strips being effected in the usualmanner by knife rollers II]. In the space between the knives of eachpair, there will remain mass which is somewhat compressed from the pointl5 (Fig. 2) at which the knives meet the mass sheet 6 and is forced outlaterally towards both sides, as indicated at IE on Fig. 1 approximatelyat the point where the circumference of the circular knife is againleaving the conveying surface.

The mass which is conducted in this manner to the regular strips will atthe same time tear the thin film, which will otherwise usually remainbetween the strips.

The effect of this arrangement is best seen on the perspective view Fig.3, from which it will be noted that the strips l2 will be left adistance apart which is sufiicient to prevent contact between the stripsowing to deformation.

I claim:

Apparatus for the treatment of plastic exnamed conveyor surface andauxiliary conveyor belts fitting between the cutting knives and passingalternately over rollers located on opposite sides of said cuttingknives for conducting cut strips from said knives on to each of the twoconveyor belts located on opposite sides of the cutting knives.

HENRICH BILLE.

